Hippopotamus are born underwater
If the baby is born underwater, the mother needs to push it to the surface to breathe. Newborn hippos are only able to hold their breath for about 40 seconds at a time. The mother stays in the water with her newborn for several days without eating, and she waits until her baby is strong enough before they dare leave the water at night to graze. Mothers nurse their babies, even underwater, for about eight months.
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